The present invention relates to a system and method for the control of the temperature maintained in the contents of storage vessels integral with an automotive, or truck, transport system by adapting portions of the existing internal combustion engine system to aid in effecting such control. Both high and low temperatures are avoided in diesel fuel, compressed air, and hydraulic oil storage vessels and lines. The system of the invention can be adapted for use either during transit or when the transport unit is at rest.
Low atmospheric temperatures have long been recognized as creating major problems for automotive transport. Diesel-powered trucks experience much difficulty in starting, fuel storage units develop plugged lines or sluggish flow of diesel oil due to greatly increased viscosity. Compressed air tanks, for use with the braking system of large trucks, experience plugged lines and inoperable valves due to formation of ice within the tank, the source of the moisture being the intake air to the compressor. Lubricating and hydraulic oil lines operate poorly because of the greatly increased viscosity of the oil employed. Other diesel-powered systems, including, for example, bulldozers and cranes, likewise encounter similar problems.
High atmospheric temperatures likewise create operational problems although these problems are generally less severe. Accordingly, little attention has been given to such problems although it is recognized that increased fuel vapor pressure may, under some circumstances, create a safety hazard.
Most attention has been given to various and elaborate schemes for improving cold-weather starting properties of diesel engines and to interior heating of cabs of trucks and general interior heating for other automotive vehicles. Most of such prior art employs, at least in part, the existing heat exchange system for cooling the automotive power unit.
Improved starting of diesel engines often involves the preheating of combustion air, as in U.S. Pat. No. 3,397,684, or external warming of engine coolant, as in U.S. Pat. No. 2,858,823. Separate combustion chambers may be employed as in U.S. Pat. No. 4,105,158 and in U.S. Pat. No. 3,795,234.
Heat exchange systems, including radiator coolant fluids, have also been employed in automotive systems for providing hot water to a recreational vehicle, as in U.S. Pat. No. 3,521,704; heating crude oil samples, as in U.S. Pat. No. 2,682,264; and warming foods, as in U.S. Pat. No. 3,874,361.
All of these approaches are intended to provide a warming function under a limited set of conditions, usually with the vehicle at rest. Little, if any, attention is paid to temperature control. Other than the cooling function of the radiator system in concert with the internal combustion engine, no attention is given to situations requiring cooling to approximately ambient temperature.
There remains a need for an effective system for controlling the storage temperatures of the various fluids employed in the operation of automotive transport and power units. This includes the effectuation of cooling, as required, as well as heating, all in response to the attendant weather conditions. This need becomes more emphatic when considered in the light of environmental and energy limitations such as those society faces presently.